Remnants of an ancient, 4-square-meter hearth in the center of Israel’s Qesem Cave turned up after three seasons of fieldwork led by archaeologist Ruth Shahack-Gross of the Weizmann Institute of Science in Rehovot, Israel. Shahack-Gross and colleagues suggest in the April Journal of Archaeological Science that the hearth was used for cooking because it lay adjacent to an area where Stone Age hominids cut up deer, wild pigs and other prey into large pieces and another spot where meat was removed from animals’ bones.

“This hearth marks a turning point — for sure in Qesem Cave but maybe also elsewhere — from sporadic to habitual use of fire,” Shahack-Gross says.

The new findings add to evidence from the last decade that hominids employed fire in multiple ways by at least 400,000 years ago, remarks archaeologist John A.J. Gowlett of the University of Liverpool in England. Gowlett and his colleagues have unearthed more than a dozen small hearths at England’s 400,000-year-old Beeches Pit site. Burned, broken stone cutting implements found in and around these hearths suggest that ancient residents sat by fires while making tools.

Meanwhile, investigations in Spain’s Bolomor Cave have uncovered small hearths where Neandertal ancestors cooked rabbits, tortoises and other small animals roughly 228,000 years ago.

The identity of the ancient fire makers at Qesem Cave is unknown. Hominid teeth previously unearthed in the cave belonged to a possible Homo sapiens precursor, the investigators say.

“It’s very interesting to see more definitively that ancestors of both modern humans and Neandertals used fire in complex ways,” Gowlett says.

Qesem Cave contains a hearth of unprecedented size for its time, Shahack-Gross says. Rocks partially line the structure. Microscopic analyses determined that two ashy sediment layers contained burned bits of animal bone, wood and limestone that had been heated at high temperatures, often in excess of 500° Celsius.

Each ash layer represents repeated instances of setting fires in the hearth, the researchers say.

Stone tools suitable for slicing meat off bones were found in and around the Qesem fireplace. Larger tools scattered a few meters away were more appropriate for butchering carcasses. Burned animal bones uncovered among these artifacts further suggest that meat was cooked.

Between 420,000 and 300,000 years ago, Qesem Cave’s earliest inhabitants left traces of occasional small campfires. That era abruptly ended when locals reconfigured the cave as a food-processing center organized around a large fireplace, Shahack-Gross proposes.

An ancient transition to regular fire building at appointed spots transformed social life, Gowlett argues. Because cooking improves digestion of nutrients, hominids could have spent less time foraging and hunting. And increased opportunities for socializing around fires shifted language evolution into high gear, he suggests.